Make column indexed

Using ADOX I'm able to add an AutoIncrement column to an MS Access table. I'd like to make it indexed as well. Tricks and tips? Any place to see the constants like AutoIncrement?
with col do
begin
ParentCatalog := cat;
Name := fName;
Type_ := adInteger;
Properties['AutoIncrement'].Value := true;
//Properties['indexed'].Value := true; <==============
table.Columns.Append(col, Unassigned, Unassigned);
end;
Thanks, Mike
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